Volume, gain and output level

Analog stage, outputs and amplification

Answers on this topic

• Can DAVE drive power amplifiers directly, and is its DAC mode any different from pre-amp mode at -3 dB?
• Is Chord's digital volume control transparent, and does it lose resolution at low volume?
• Is M Scaler pass-through bit perfect, and why is the scaled output quieter?
• Should I use a pre-amp (tube or solid state), or run the Chord DAC straight into a power amp?
• What do the colored indicators mean (volume, sample rate, charging), and is a volume color the same level across Chord DACs?
• Which output level should I feed my amp: Qutest's 1, 2 or 3 V setting, TT2's DAC mode or gain, or the volume control?

Everything he said on this topic (151)

One-line summaries in our words, oldest first. Each link opens the original.

• 2014-04-18Watts explains Hugo's volume preset mode came from matching Qute for comparisons, and that the settings-memory feature was dropped because the FPGA was full after adding crossfeed and DSD. Head-Fi, Apr 2014
• 2014-05-17Watts says each volume color covers 3 steps of 1dB, a compromise between range and distinguishable colors. Head-Fi, May 2014
• 2014-05-17Watts says the volume steps are in dB, so two colors double or halve the output, giving the same resolution whatever the headphone sensitivity. Head-Fi, May 2014
• 2014-05-22Watts says the digital volume control is precise in dB, so a low volume setting with IEMs makes no difference. Head-Fi, May 2014
• 2014-06-09Watts measures 2.996V RMS at 0dBFS in preset mode and 2.112V RMS at violet, and advises feeding power amps directly without a pre-amp. Head-Fi, Jun 2014
• 2014-06-21Watts advises feeding Hugo directly to sub and power amp; active pre-amps add distortion and noise floor modulation, passive controls add wiper and dielectric absorption problems. Head-Fi, Jun 2014
• 2014-07-26Watts says Hugo outputs up to 5V RMS with a 3V preset, advises dropping the pre-amp, and describes damping-factor tests and Hugo's 0.075 ohm output impedance. Head-Fi, Jul 2014
• 2014-09-02Watts gives Hugo's volume colors in dB: each color typically covers three 1 dB levels, white covers 0 to +18dB, and the -4dB preset gives 3V RMS to match Qute. Head-Fi, Sep 2014
• 2014-09-02Watts says the manual's 2V RMS preset figure will be corrected to 3V RMS in the next print run. Head-Fi, Sep 2014
• 2014-09-03Watts confirms another poster and lists output voltages at each level, noting Hugo clips at +18dB giving 5.25V RMS maximum. Head-Fi, Sep 2014
• 2014-09-09Watts says if JRiver's volume control is properly dithered when truncating, there is no distortion or transparency loss to worry about. Head-Fi, Sep 2014
• 2014-09-11Watts says high power-amp gain is still better than adding a pre-amp, and he runs at green to azure into amps needing 1V RMS for full power. Head-Fi, Sep 2014
• 2014-10-12Watts says yes if it does not overload or add distortion, notes the attenuator can matter, and suggests trying both and using Hugo's higher output if no difference. needs context Head-Fi, Oct 2014
• 2014-11-17Watts says the volume control is digital, the only way to make it completely transparent, and the release date is sometime in 2015; the product is not named. needs context Head-Fi, Nov 2014
• 2015-01-23Watts says Hugo's 51-bit volume is truncated at 16FS by noise shaping and dither, adding only fixed -180dB noise, and notes its output relay, 75 milliohm impedance and anodizing. Head-Fi, Jan 2015
• 2015-02-15Watts says DSD modulators become unstable above -6 dBFS, so Hugo's DSD filters keep that headroom and internally raise volume by +6 dB to preserve gain. Head-Fi, Feb 2015
• 2015-02-15Watts says DSD should not be quieter on Hugo, since test tones converted to DSD were level-matched to PCM and with the +6 dB boost levels were identical. Head-Fi, Feb 2015
• 2015-03-14Watts defends Hugo's color volume display, gives its range from +18 dB (white) to -70 dB (dark brown), prefers digital volume to pots, and says Project xxxx keeps the colors. Head-Fi, Mar 2015
• 2015-04-30Watts says maximum unclipped output is a little over 5V RMS into 300 ohms, the 37V figure is just a spreadsheet entry, and pressing crossfeed at power-up sets 3V RMS at 0 dBFS. Head-Fi, Apr 2015
• 2015-06-29Watts says the balanced output is +6dB over the single-ended output. needs context Head-Fi, Jun 2015
• 2015-08-29Watts says the calibrated output began as a prototype feature for listening tests against earlier DACs set to exactly 3v RMS at 0 dBFS, and was kept for DAC mode. Head-Fi, Aug 2015
• 2016-01-11Watts says Dave has 20 elements, not 16, for overload margin: -3 dB gives 3 V RMS, +3 dB 6 V RMS, and clipping starts at +4 dB. Head-Fi, Jan 2016
• 2016-03-17Watts says Dave's 12 V balanced output comes at +3 dB volume for headphone headroom, and its digital path exceeds 350 dB accuracy, so volume does not change sound. Head-Fi, Mar 2016
• 2016-03-31Watts says DAVE's volume is fully digital because analog controls have small-signal errors that degrade depth, and describes his 350 dB noise shaper and -301 dB test targets. Head-Fi, Mar 2016
• 2016-03-31Watts says DAVE's maximum attenuation is -75 dB with truncation noise near -350 dB, and explains how noise shapers attenuate signals near their resolution, harming depth. Head-Fi, Mar 2016
• 2016-05-17Watts says DAVE's DAC mode equals pre-amp mode with volume fixed at -3 dB (3 V RMS), and DAVE clips only above +4 dB, which gives 6.7 V RMS. Head-Fi, May 2016
• 2016-12-27Watts advises not worrying if the volume is at +4dB or below, and suggests Audacity to check a recording's peak levels. Head-Fi, Dec 2016
• 2017-04-12Watts says output voltage into 300 ohms and volume colors match Mojo, the wheel has no click steps and shows two colors, and the remote steps volume. Head-Fi, Apr 2017
• 2017-04-12Watts says it remembers all settings except the 3 V preset, which holds until the volume is adjusted. Head-Fi, Apr 2017
• 2017-08-03Watts says there is no danger of clipping even at +7 dB when using Blu 2, so clipping is only possible at +8 dB. needs context Head-Fi, Aug 2017
• 2017-08-03Watts says +4 dB volume is fine with DAVE on its own. Head-Fi, Aug 2017
• 2017-08-03Watts says material peaking at -1 dBFS allows +5 dB on DAVE without clipping, but sources reaching 0 dBFS will clip. Head-Fi, Aug 2017
• 2017-08-03Watts explains that 0 dBFS is the PCM maximum, so quiet recordings that never reach it will not clip with volume above +4 dB; clipping is heard as hardening. Head-Fi, Aug 2017
• 2017-10-24Watts suggests using DAVE's balanced output and its volume control to avoid driving the ADAM speakers with too high a voltage. Head-Fi, Oct 2017
• 2017-10-25Watts says DAVE's data path from input to pulse array is better than 350 dB, so no truncation occurs and large volume changes do not affect detail or depth. Head-Fi, Oct 2017
• 2017-10-31Watts says DAVE at -3 dB gives 3 V RMS, -10 dB gives 1.34 V RMS, and setting -6 on the display gives about 2.1 V maximum. Head-Fi, Oct 2017
• 2017-11-16Watts says if a Chord DAC's volume is not at full white the output is never voltage limited, so extra voltage headroom makes no difference. Head-Fi, Nov 2017
• 2017-11-30Watts says three clicks down on the remote will set the output to 2.12V. needs context Head-Fi, Nov 2017
• 2018-01-09Watts says Qutest ships with a 2A supply but works on 1A 5V; pressing both buttons during the rainbow start-up sets output voltage, otherwise it changes display brightness. Head-Fi, Jan 2018
• 2018-01-13Watts says it is done digitally with Hugo 2's volume control, whose aggressively noise-shaped truncation gives -400 dB accuracy, and 0dBFS is below the noise shaper's maximum modulation. needs context Head-Fi, Jan 2018
• 2018-01-14Watts says volume is implemented in Hugo 2 exactly as in Dave. Head-Fi, Jan 2018
• 2018-01-17Watts says Qutest's noise is identical at every output setting and the 3V figure reflects distortion; the best setting depends on the amp, e.g. 1v for a 1.2v-rated amp. Head-Fi, Jan 2018
• 2018-02-09Watts says in Blu 2 truncator tests TPDF dither sounded worst, losing depth, and Gaussian came halfway to noise shaping; he suspects software volume beats analog volume. Head-Fi, Feb 2018
• 2018-02-11Watts says passive volume controls add small-signal non-linearity via contacts and joints, conventional R2R and delta-sigma DACs resolve small signals poorly, so he ensures -301 dB resolution. Head-Fi, Feb 2018
• 2018-02-11Watts says Hugo 2's volume uses aggressive noise shaping at 705/768 kHz to stay below -350dB, preserving depth; software volume degrades depth less than an analog volume control. Head-Fi, Feb 2018
• 2018-02-22Watts says DAVE at -3 dB gives exactly 3 V RMS at 0 dBFS, Chord's historical reference level, while 0 dB matches Hugo at 4.24 V RMS. Head-Fi, Feb 2018
• 2018-02-24Watts says Harrison attenuators, rated for a 600 ohm source with a 2.5k ohm load, suit 2Qute; run the longer cable to the attenuator and keep it near the amp. Head-Fi, Feb 2018
• 2018-03-06Watts says 2Qute outputs 3.0V RMS at 0dBFS, exactly the same as Qutest at its 3.0V setting. Head-Fi, Mar 2018
• 2018-03-06Watts says Qutest and 2Qute have identical discrete output stages and the same 3V output, suggesting Qutest's greater refinement may make a difference more apparent. Head-Fi, Mar 2018
• 2018-03-16Watts says at -3 dB the balanced output is 6 V RMS across plus and minus, clipping is 13.6 V RMS, and output impedance is 33 ohms. Head-Fi, Mar 2018
• 2018-03-22Watts explains the 2.75dB WTA overload margin, delays audio in JRiver to keep 1M taps with video, describes visible noise floor modulation, and gives DAVE and Hugo 2 level limits. Head-Fi, Mar 2018
• 2018-03-28Watts says 1V RMS against 3V RMS is -9.54 dB, so 9 clicks (1.06V) or 10 clicks (0.95V) down. Head-Fi, Mar 2018
• 2018-04-19Watts says the best output level depends on the pre-amp's topology, as 3v may cause distortion in some; without PA20 experience, he advises trying levels by ear. Head-Fi, Apr 2018
• 2018-05-11Watts gives just over 18V RMS at 1% THD in amp mode and 5V in DAC mode, estimates 98 dB from LS3/5a speakers, and explains why supercaps replace batteries. Head-Fi, May 2018
• 2018-05-12Watts lists TT2 output options (DAC mode 2.5V RCA/5V XLR, low gain 3V, volume at -3dB) and recounts how the DX amp's output stage was adopted in TT2. Head-Fi, May 2018
• 2018-05-15Watts says amp mode on TT2 is for driving efficient speakers or replacing a pre-amp as a digital pre-amp, and suggests low gain mode for that. Head-Fi, May 2018
• 2018-05-22Watts explains TT2's digital DC servo with no coupling caps, confirms separate crossfeed for headphone and amp/DAC modes, and says -3dB volume equals 3V RMS as on Dave. Head-Fi, May 2018
• 2018-05-25Watts says TT2's output stage uses emitter degeneration and safety resistors, and will not clip at or below +6dB with CD into 8 ohms SE, or +12 dB with Blu-ray. Head-Fi, May 2018
• 2018-06-17Watts says TT2's gain control applies to all outputs with separate remembered settings, and low gain limits output to 2.5V RMS and lowers residual noise for IEMs and power amps. Head-Fi, Jun 2018
• 2018-06-17Watts says BluDave cannot voltage clip at +6dB but can current limit into 8 ohms (4.1V RMS, 2.1W), making +5dB the danger zone; quiet recordings may explain the poster's level. Head-Fi, Jun 2018
• 2018-07-02Watts says extra headroom would matter only if Roon altered the file; with bit perfect files the WTA1's 2.76dB overload margin cannot be exceeded. Head-Fi, Jul 2018
• 2018-07-05Watts says noise is identical across the three voltage settings because the adjustment is digital; the right setting depends on the connected amp's overload behavior. Head-Fi, Jul 2018
• 2018-08-19Watts says none of his DACs send or receive volume control data over USB. Head-Fi, Aug 2018
• 2018-08-23Watts confirms DAC mode makes no difference to the signal path; it only sets the volume to -3dB and disables volume changes. Head-Fi, Aug 2018
• 2018-09-02Watts says TT2 gives 9.3V RMS at +7dB with 0dBFS, digital gain extends to +22 dB, and low gain cuts output by 9dB, including on headphone outputs. Head-Fi, Sep 2018
• 2018-09-16Watts says TT2 has a gain switch because its high power would leave too much noise for sensitive IEMs; low gain cuts residual noise to 1.7 uV. Head-Fi, Sep 2018
• 2018-10-03Watts explains TT2's single-stage SE output amplifier, the relay-switched resistor that sets low gain, and the inverted stage that creates the balanced negative output. Head-Fi, Oct 2018
• 2018-10-27Watts says 10 versus 20 pulse array elements helps Dave's transparency, and his noise-shaped volume control is not bit perfect but passes a -301 dB test. Head-Fi, Oct 2018
• 2018-10-28Watts explains how TT2's volume display shifts with gain mode and where it clips, and gives delays of 34 ms for Hugo 1 and 63 ms for TT2 with video. Head-Fi, Oct 2018
• 2018-11-02Watts says it matches Blu 2 with 3 dB headroom, pass-through is volume matched, the main change is musical and takes time, and the supplied SMPSU is fine. Head-Fi, Nov 2018
• 2018-11-17Watts says he always uses high gain, and low gain is for when lower noise is needed. Head-Fi, Nov 2018
• 2018-11-18Watts says TT2 needs no balance control with digital volume, a 705/768 indication means the M Scaler works, and suggests a week of listening before comparing pass-through. Head-Fi, Nov 2018
• 2018-12-12Watts says TT2's linear output current suits efficient speakers; it gives 7 W, or 18 W into 8 ohms balanced, and has a low-noise low gain mode for IEMs. Pursuit Perfect System 39:38
• 2018-12-16Watts says TT2 keeps DAVE's -3 dB equals 3 V RMS convention, clipping at +7 dB; CD cannot clip at +6 dB, with M scaler +10 dB, Blu-ray +13 dB. Head-Fi, Dec 2018
• 2018-12-17Watts says 2 V is 3.5 dB and 1 V 9.5 dB below 3 V; non-WTA upsamplers cannot predict the M Scaler, as longer conventional filters add near-zero coefficients. Head-Fi, Dec 2018
• 2019-01-09Watts gives TT2 distortion figures, 0.042 ohm output impedance and low-gain voltages, notes no distortion above 3 kHz at 12 W, and says the FPGA sits die-down on the chassis. Head-Fi, Jan 2019
• 2019-01-10Watts says distortion does not differ between TT2 gain modes below clipping, and to use high gain above 2.5 V single-ended or 5 V XLR. Head-Fi, Jan 2019
• 2019-01-10Watts says TT2's volume settings match DAVE's, with 0 dB at 4.23 V RMS, so it cannot clip below +6 dB in high gain. needs context Head-Fi, Jan 2019
• 2019-01-12Watts says TT2's XLR output in low gain is slightly higher than Hugo 2's, 6.6 against 5.4 V RMS. Head-Fi, Jan 2019
• 2019-01-20Watts says Qutest's output levels are set digitally through one noise-shaped stage at -400 dB accuracy, so audible differences come from ancillary gear; if unsure, use 2 V. Head-Fi, Jan 2019
• 2019-01-23Watts says TT2's amp mode and headphone mode use identical hardware apart from connectors and FPGA configuration, so output is the same with identical settings. Head-Fi, Jan 2019
• 2019-03-06Watts says low gain was intended for efficient IEMs, he runs normal headphones in high gain, and DAC mode is set to low gain, which he guesses is most appropriate for driving power amps directly. Head-Fi, Mar 2019
• 2019-03-12Watts says to consider TT2's balanced output only at +6H or above, and its low gain setting is about 6 dB quieter than Mojo. Head-Fi, Mar 2019
• 2019-04-10Watts explains TT2's volume display shows absolute output, so switching gain changes the reading by 9 dB, and gives clipping points of -2L and +7H. Head-Fi, Apr 2019
• 2019-04-11Watts says TT2's gain switch changes the output amplifier's gain, giving just over 3 V RMS low and 9.3 V RMS high, with the volume calibrated to actual output. Head-Fi, Apr 2019
• 2019-04-11Watts says TT2's balanced output gives double the voltage, so -3H is 6 V and +6H is 16.92 V RMS balanced. Head-Fi, Apr 2019
• 2019-04-19Watts says Dave cannot clip below +3 dB on the volume control, or +6dB with the M scaler attached. Head-Fi, Apr 2019
• 2019-04-23Watts says TT2's low gain mode has lower residual noise, but the difference is inaudible through a power amp. Head-Fi, Apr 2019
• 2019-06-01Watts finds the reported problem odd, perhaps an EMC issue with the Fostex, and suggests low gain mode, where -3L cannot clip, since the poster runs at -20H. needs context Head-Fi, Jun 2019
• 2019-06-10Watts says TT2 supplies the same current in both gain modes for the same voltage and load, but low gain is limited to about 3 V RMS, 1.5 A into 2 ohms. Head-Fi, Jun 2019
• 2019-10-09Watts says DAC mode is identical to amp mode at -5L, one amplifier does I-to-V, filtering and buffering, and gain changes mute 16 seconds while the DC servo settles. Head-Fi, Oct 2019
• 2019-10-10Watts says TT2's digital gain reaches +18 dB, low gain clips above 3.3 V RMS at -2 dB, and high gain allows 9.4 V RMS, safe to +6 dB. Head-Fi, Oct 2019
• 2019-11-18Watts confirms the manual: red is 1 V, green 2 V, blue 3 V. Head-Fi, Nov 2019
• 2020-01-18Watts says Hugo 2 is Class A into 300 ohms at 5v RMS, AB into lower loads, and explains DSD volume needs another noise shaper because DSD is 1-bit PCM. Head-Fi, Jan 2020
• 2020-01-24Watts says M scaler/Dave can run at +9dB without clipping into loads above 16 ohms, and there is no news on the amps as he has been busy. Head-Fi, Jan 2020
• 2020-02-03Watts says Qutest's 2 V and 3 V settings do not differ significantly internally, so audible changes come from the pre-amp or power amp. Head-Fi, Feb 2020
• 2020-02-22Watts finds TT2 slightly warmer in high gain, says not to exceed -3L in low gain, to match volume numbers when comparing, and low gain is for IEMs. Head-Fi, Feb 2020
• 2020-02-22Watts says TT2's low gain only lowers residual noise, audible only with sensitive IEMs, and both modes measure nearly identically at -3 or lower. Head-Fi, Feb 2020
• 2020-02-24Watts says TT2's amp mode and headphone mode differ only in active connectors and remembered settings, so gain settings are identical. Head-Fi, Feb 2020
• 2020-02-24Watts says TT2's DAC mode equals amp mode at -3L, since DAC mode is fixed in low gain, and adds that darker is better. Head-Fi, Feb 2020
• 2020-02-24Watts corrects himself: TT2's DAC mode is 2.5 V, the knee of the low-gain distortion curve, as 3 V can be too hot for many pre-amps. Head-Fi, Feb 2020
• 2020-03-09Watts says Qutest has no volume control, explains truncation, Gaussian dither and 11th-order noise shaping at 705/768 kHz, and prefers Roon volume over a pre-amp. Head-Fi, Mar 2020
• 2020-03-12Watts says Hugo 2 batteries are robust, advises using its own volume rather than a passive, and says certified USB cables suffice; heard differences are placebo or RF noise. Head-Fi, Mar 2020
• 2020-06-04Watts says TT2 matches Mojo and DAVE: -3dB is 3V RMS and four remote clicks down gives 1.89V RMS; with an M scaler set -4, as it attenuates 2.75 dB. Head-Fi, Jun 2020
• 2020-07-27Watts says TT2 can stay on 24/7, DAC mode equals low gain at -5L, and an external amp often sounds warmer from distortion and capacitor dielectric absorption. Head-Fi, Jul 2020
• 2020-07-28Watts says low gain sounds slightly different from high gain due to two extra feedback components, and ASIO is preferred for DSD512, possibly with less processing than WASAPI. Head-Fi, Jul 2020
• 2020-07-28Watts gives TT2 levels (-5L is 2.4V RMS, 0H 4.2V), calculates supercap life at 500,000 hours, and says leaving it on aids reliability. Head-Fi, Jul 2020
• 2020-10-20Watts gives output levels at 0dBFS: -6 is 2.12V RMS RCA and 4.25V XLR; -7 is 1.89V RCA and 3.79V XLR. needs context Head-Fi, Oct 2020
• 2021-04-06Watts says volume colors mean the same voltage across DAVE, TT2, Hugo 2 and Mojo (blue is 1.0V RMS), and all desktop DACs have galvanically isolated USB. Head-Fi, Apr 2021
• 2021-04-30Watts says balanced XLR doubles the voltage into a power amp, a +6dB change, and Dave's XLR outputs are for pre or power amps only, not headphones. Head-Fi, Apr 2021
• 2021-05-10Watts says the M scaler exposes recording defects by being more transparent, and inter-sample clipping is handled by a -2.76dB gain reduction on all outputs, including pass-through. Head-Fi, May 2021
• 2021-07-23Watts says the volume control output is aggressively noise shaped, not truncated or dithered, reproducing -301dB within +/-0.001 dB, and shows the M scaler truncator's -390dB noise floor. Head-Fi, Jul 2021
• 2021-08-19Watts says Opto-DX isolates fully only with batteries on both sides, and calls his volume truncation noise-shapers subjectively lossless but not bit perfect, a claim he is researching. Head-Fi, Aug 2021
• 2021-09-09Watts says WTA benefits shrink at higher frequencies because transient error area falls fourfold per sample-rate doubling; DAC and pre-amp modes perform identically; studio ADCs will have phantom power. Head-Fi, Sep 2021
• 2021-09-11Watts says TT2 at +0H gives about 2.25W into 8 ohms, +7H 7W; CDs clip above +7H, but sources with 6dB margin allow +12H, even +18H on his 803D3s. Head-Fi, Sep 2021
• 2022-01-04Watts says Dave drives the Susvara to 92 dB SPL, voltage limited, and gives volume limits (+4 solo, +7 with M scaler); preferring an amp means preferring distortion. Head-Fi, Jan 2022
• 2022-01-31Watts says one reason for dropping line-level startup was users forgetting it, powering up, plugging in IEMs and blowing their ears out. Darko.Audio 17:18
• 2022-01-31Watts says other reasons were simplifying setup alongside the new DSP and that Mojo's 3 volts is too much for many amplifiers, hence Qutest's 1, 2 and 3 volt settings. Darko.Audio 17:48
• 2022-01-31Watts says yes, and that his Mojo 2 presentation publishes what each volume color means in voltage. Darko.Audio 18:48
• 2022-02-01Watts says he dropped the feature because many used IEMs in line-level mode, 3V was too hot for some pre-amps, and he wanted simple controls. needs context Head-Fi, Feb 2022
• 2022-02-08Watts says the UHD DSP has 3 overload bits so EQ never clips internally, but boosts require lower volume: Mojo 2 can clip at white, or violet with +6 dB. Head-Fi, Feb 2022
• 2022-02-22Watts says RF only degrades low-level linearity if signal-correlated, his DACs' RF output is low and uncorrelated, and analog pre-amps add coloration rather than beating Chord's volume control. Head-Fi, Feb 2022
• 2022-03-19Watts says the test used +9 dB at 20 Hz, -9 dB at 20 kHz and a 6 kHz sine; volume now spans -108 to +18 dB for sensitive IEMs. MFG Audio Reviews 39:06
• 2022-03-19Watts says an indicator shows whether the volume is in the high or low range, and begins on the bass tone controls. MFG Audio Reviews 39:52
• 2022-03-31Watts says 32-bit integer reaches TT2's FPGA but 32-bit float is unsupported; he runs TT2 at +7 via M scaler, and Utopia needs high gain, low gain suiting IEMs. Head-Fi, Mar 2022
• 2022-04-04Watts says WTA1 filters carry 2.76 dB of overload headroom for Gibbs ringing and inter-sample overs (measured worst cases 2.41 dB and 3 dB); a single 0.8dB clip was inaudible. Head-Fi, Apr 2022
• 2022-04-10Watts says Chord DACs have no balance control because digital volume needs no channel matching, but he could add one to future products if demanded. Head-Fi, Apr 2022
• 2022-04-25Watts says TT2 and M Scaler can be stacked, but are better apart with Wave or solid-ferrite BNC cables; use high gain unless IEMs hiss; avoid wireless subwoofer links. Head-Fi, Apr 2022
• 2022-04-26Watts advises high gain into a power amp, keeping units on Wave cables apart to avoid capacitive coupling and cable ends touching, and says TT2 tolerates running warm continuously. Head-Fi, Apr 2022
• 2022-04-27Watts says he designed his own for the ADCs, video leaves headroom to go above white without clipping, and Hugo 2 and Mojo 2 give the Stealth ample volume. Head-Fi, Apr 2022
• 2022-04-28Watts confirms DAC mode is identical to pre-amp mode fixed at -3dB, so pre-amp mode at -3dB gives identical performance. Head-Fi, Apr 2022
• 2022-05-18Watts quotes his Mojo 2 presentation: for 2 V output, set both volume LEDs to indigo. Head-Fi, May 2022
• 2022-07-01Watts says his slide is correct: 3 V is too hot for many pre-amps or integrated amps, blue is more appropriate, and use it if it sounds smoother. Head-Fi, Jul 2022
• 2022-07-19Watts says TT2 has no line output: single-ended is volume-adjusted from 0 to 9V RMS and XLR doubles that to 18V, so a sub can be fed from either. Head-Fi, Jul 2022
• 2022-07-19Watts says a sub's line-level and speaker-level inputs both feed its power amp, an easy load for TT2, and guesses speaker level is best since less attenuation is the goal. Head-Fi, Jul 2022
• 2022-10-01Watts says that when running with the M scaler the limit is +10dB, where a 0dBFS signal clips into a nominal 8 ohm load. needs context Head-Fi, Oct 2022
• 2022-12-01Watts says Mojo 2 has no analog gain change; he raised volume steps from 96 to 128 for sensitive IEMs, with the menu button showing high or low range. Head-Fi, Dec 2022
• 2023-03-12Watts says some amps are overloaded by a 3V input, raising distortion and sounding harder without clipping, which is why Qutest has three output voltage settings. Head-Fi, Mar 2023
• 2023-03-28Watts says PCM also allows EQ, crossfeed and digital volume, which DSD cannot; analog volume adds problems, and his volume controls are transparent, passing the -301 dB test. The Headphone Show 53:18
• 2023-03-30Watts gives Stealth SPL at 0dBFS (98.3 dB Hugo/Mojo, 100.0 Dave, 103.4 TT2 headphone, 109.1 balanced), warns against long listening above 80dB, and suggests volume settings. Head-Fi, Mar 2023
• 2023-05-04Watts says inter-sample overloads are very unlikely with music, and his -2.73dB overload margin covers Gibbs overshoot and suits his SPDIF de-emphasis filter. Head-Fi, May 2023
• 2023-05-20Watts says improving DAVE prototype harmonics from -120 dB to below -150 dB sounded brighter and more transparent; white volume cannot clip but deeper can, at ear-damaging levels. Head-Fi, May 2023
• 2023-09-24Watts says output level changes are made digitally, not with analog resistors and switches, without changing amplitude or phase (0.001dB, 0.001 deg) for his -301dB test signal. Head-Fi, Sep 2023
• 2023-09-24Watts says the 3v setting also has some attenuation, tuned for best dynamic range and lowest output distortion, while 2v and 1v add a bit more. Head-Fi, Sep 2023
• 2023-12-17Watts says streamer-controlled DAC volume needs a Chord request and a USB decoder command stream, raises master-volume issues, and is not planned for Ultima. Head-Fi, Dec 2023
• 2024-01-14Watts says Chord's 3 V standard dates from 1990s passive pre-amps, Qutest added 1/2/3 V options, and a Mojo 2 line-level output was dropped to keep controls simple. Head-Fi, Jan 2024
• 2024-03-02Watts says that so long as the volume is not white it cannot clip, even with the maximum digital input of 0dBFS. Head-Fi, Mar 2024
• 2024-11-11Watts says the safe setting depends on the source: AV material has headroom to run at +14 without clipping, while CD clips at +10, so +9 or below is fine. needs context Head-Fi, Nov 2024
• 2024-12-11Watts says both indicators must be white for clipping, assuming no boost EQ; with +3dB EQ, go three steps down to avoid clipping at 0dBFS. needs context Head-Fi, Dec 2024
• 2025-03-17Watts advises reducing the setting by some dB, suggesting +7dB as the limit with a Hugo M Scaler. needs context Head-Fi, Mar 2025
• 2026-03-24Watts says volume and EQ settings are now remembered separately for the 4.4 mm and 3.5 mm outputs, for owners using Mojo 2 at high volume on a desktop and with IEMs on the move. Audio Force 33:44